Conventionally, a large-scale system as in a distributed computer system such as a large-scale data center changes hardware in charge of processing, in other words, migrates a process to different hardware to increase the availability of the system. As an example, a technology for running a VM (Virtual Machine) host on hardware and running a VM guest on the VM host is known.
The VM host is a program that virtually realizes the operating environment of a computer system. The VM guest runs as a virtual machine in an environment provided by the VM host, and takes a process to be provided to a user. The VM guest can continue the process even if it is migrated to a different VM host.
Used as a technology for migrating a VM guest to a different VM host in this manner is migration such as live migration that migrates the VM guest without stopping its operation and cold migration that migrates the VM guest after stopping its operation. Migration is used, not limited for the VM guest but also when the VM host is migrated to another physical server.
For example, a technology has conventionally been used in which GUI (Graphical User Interface), CLI (Command line interface), Script, or the like is used to specify a migration destination VM host and migrate migration target VM guests one at a time.
In recent years, a technology for executing an automatic migration is also known. For example, a technology is known in which virtual software on a server to which a VM guest may migrate is identified based on the CPU usage rates, memory usage amounts, duration of migrations of servers targeted as migration destinations of the VM guest, and the migration target VM guest is live-migrated to the identified virtual software.
Moreover, a technology is also known in which scheduling is performed based on the load cycle of a virtual machine system on which a VM host and a VM guest run, and live migration is automatically executed in accordance with the schedule.
With regard to the conventional technologies, see Japanese Laid-open Patent Publication No. 2008-217302, Japanese Laid-open Patent Publication No. 2010-117760, and Japanese National Publication of International Patent Application No. 2007-536657, for example.
However, if a plurality of virtual machines is migration targets in the conventional technology, the virtual machines are migrated one at a time and the completion of the migration of each virtual machine is confirmed. Therefore, there are problems that the work of a manager who manages a migration process of the virtual machines becomes complicated, and the time to bind the manager is long.
For example, a technology using a GUI, a command and the like specifies a migration destination VM host, executes live migration, and confirms whether or not live migration has ended normally, for each migration target VM guest. In other words, live migration is not able to be successively executed. Hence, the manager is to be bound until migrations of all VM guests are completed normally.
Moreover, if live migration is automated in accordance with a schedule and the like, when a migration target VM guest is being suspended, live migration results in an abnormal termination. As a consequence, a process may end without migrating a VM guest that is desired to be migrated. In other words, also in the case of automatic execution, the manager confirms a normal termination after the automatic execution and the manager is consequently to be bound from after the execution to the confirmation of a normal termination. Therefore, even if the technology is used, the working time of the manager is not short.